From the Super Mario Wiki
Retrieved from "https://www.mariowiki.com/index.php?title=Level_B-2&oldid=2698848"
The course is a maze containing Ladders and Red Girder Rivets. The Cursed Mini Mario starts in the top left and, without the player's input, begins marching around on the level's Ladders and platforms. The Mini Peach starts on a lone platform and must first make its way to the pair of Hammers at the top of the stage and hit the Cursed Mini Mario with them to turn the toy into a normal Mini Mario. A few Girder Pickups can be collected to increase the number of Red Girders in the player's inventory, which, among other things, can be used to confine the Cursed Mini Mario before attacking it. Both Minis should then head to the Goal Door, located in the bottom left beyond a short pit of spikes.
The M Coin is located in a tunnel right under Mini Peach's starting position. The player must use Red Girders to guide the Mini to the coin.